Gear-pump.



G. A. WOOD.

GEAR PUMP.

APPLICATION FILED Amma. me.

Patented July 9, 1918.

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` leakage is very apt to occur at any GARFIELD A. woon, or nnriiorr,MICHIGAN.

GEAR-PUMP.

Specification of Letters Patent.

Original application led Hatch 16, 1915, Serial No. 14,479. Divided andthis application tiled August 2B,

To all whom t may coment.' Be it known that I, GARFIELD A. Woon, acitizen ofthe United-States and residing at Detroit, in thecounty ofWayne and State of Michi an, have invented a new and I mroved ear-Pump,of which the following is a specification.

This application isa division of my rior application .filed March 15,1915, rial Number 14,479.

In the use of gear oil pumps much diiiculty is experienced due to thefact that the pressure of the liquid becomes equalized on all parts ofthe gear shaft bearings, thus preventing circulation and causing them torun dry; and, in high pressure installations,

om where one of the shafts passes throng the pump casing. One object ofthe present invention is to provide a passage or passages leading fromthe suction side of the pump to the vicinity of the outer .ends of thebearings, whereby a constant circulation of liquid through the bearingsis insured, and whereby, in those instances in which the shaft passesthrough the casing, leakage is vented.

The nature of the invention will more fully v'apiear from thedescription and appended rawings, wherein' two embodiments are shown.

` In the drawings, Figure isa side vew vof one embodiment of minvention, parts being broken away and t e gearsv and gear shafts beingremoved. Fig. 2 is a central v transverse section corresponding to Fig.1.

. Fig. 3 is a fragmentary section similar to Fig. 1 show' the gears inposition. Fig.

.4 is a longitu inal section through a bus in for the bearing in which..the projecting en of the drivin shaft is supported. Fig. 5 is a sectionont e line 5-5 o Fig. 4.

In the embodiment of my invention shown, the body 1 of the pum casingand the cover 2 are provided wit the alined bearing boxes 3 and 4 forthe driven pump gear, and with the alined bearing boxes 5 and 6 for thedriving ear, the three first mentioned boxes being c osed at their outerends, and the box 6 being threaded to receive the stuiling box 7 ofordinary construction. The boxes 3, 4 and 5 are lined with the bushings8, each of which has a longitudinal oil admission groove 9 formed in its65 inner surface and a similar oil exit passage pre- 1916. Serial No.117,235.

10 on the side op osite the inlet groove; and

the box 6 is line with a bushi `12 having an oil inlet groove 15 and anexit' oove 16 -that may be diametrically relate to each other. The lastmentioned grooves preferably terminate slightly. inwardly from the outeredge of the bushing4 and are joined by the circumferential roove17. Theinlet passages 9 and 15 may e omitted in certain instances as .in highpressure pumps the leakage through the bearing is suilicient toaccomplish the purpose.

`Mounted in the oppositely located bushings 8 is a shaft 21 upon whichis keyed the driven gear 22 of the pump); and the third bushing 8,vtogether with t e bushin 12, supports the driving shaft 23 to whic thedriving pump gear 24 is keyed. The shaft 23 extends `outwardly throu hthe stuiiing boxv 7 and receives its tor uerom a sprocket wheel 26, orother pre erred element. It will be seen that the shafts 21 and 23terminate some distance from the outer walls of the bearing boxes 3, 4and 5; the s aces between the ends of the shafts and t e walls of theboxes therefore constituteadmission' to the tion indicated by the'arrows in Fig. 3. The.

body of the casing is provided with the intake passage 29 and from whichbranch -the 90 feed passa e 3l and the discharge passage 32 that lea resectively, to the suction and pressure sides o the gears; and at theintersection `of the three passages a three-way valve 33 is interposed,the valve shaft 34 of which passes through the stuiiing box and hassecured thereto the operatin lever 36. The discharge passage 32 also leas th h an opening 38 to a nipple 39, from which t e liquid may beconducted by a pipe 43. l

It will be observed (Fig. 3) that the end faces of the gears 22 and 24are traversed by narrow grooves 45. The faces being otherwise in closeengagement with the walls of the casing, it` follows that the highpressure on the discharge side of the gears is tion on the intake sideis principallyeilec-v tive on the passages 10-16 likewise only when thegrooves register therewith. This construction insures a roper feeding ofthe oil to the bearings without an objectionable leakage. e

In order to connect the grooves 10 and 16 to the suction passage 31, thebody 1 is grooved as indicated at (Fig. 1), and the cover 2 is providedywith simllar grooves not shown) and the body and cover are mi led outor grooved at 51.. and 52 respectively, to allow the escape of liquidfrom the end of the gears as vthe teeth 28 enga e with each other,whereby locking of t e gears is avisided' 1 t' h 1 3a proper y mampu amg t e va ve the 5liquid may be (1st) drawn in through passage -29 anddelivered through pipe 43, or (2nd) allowed to by-pass the gears in thereverse direction, that is, from pipe 43 to assage 29 through passage32, or (3rd) alowed to continually circulate in the passages 3'1-32 asshown.

The pump may have lugs 75 for the reception of bolts 76, whereby it maybe at-l tached to an desired support 77.

It is clear t at many chan es may be made in the details of constructlonwithout departing vfrom the spirit of my invention, I do not therefore,wish to be limited otherwise than as indicated by vthe subjoined claims.

1. A gear. pump comprising in combination, -a pump casing, a pair ofmeshing pump gears within the casing, said casing having formed thereinsuction and delivery passages for liquid pumped by the gears, a pair ofshafts for the gears mounted in bearing relation to the casing, andmeans entirely Within the casing for forming communication between aportion of the suction passage and a point in one of the bearingsremoved from the corresponding gear, said means including a grooveformed in the end face of the gear whereby liquid passing from thedelivery passage into the bearing may 'be withdrawn to insure propercirculation.

2. A gear pump comprising in combination, a pump casing, a pair. ofmeshing pump gears within the casing, said casing having formed thereinsuction and delivery passages forliquid pumped by the gears, a pair ofshafts for the gears mounted in bearing relation to the casing, meansfor forming communication between one of the first named passages and apoint in one of the bearings removed from the corresponding ear, saidmeans including a groove formed 1n the corresponding end face of saidgear.

3. A gear pump comprising in combination, a pump casing, a pair ofmeshing pump gears within the casing, said casing having formed thereinsuction and delivery .passages for liquid pumped by the ears, a pair ofshafts for the gears' mounte in bearing relation to the casing, one ofthe bearings for the gears having longitudinal grooves therein, onecorrespondin to the suction passage for the gears an one to thedischarge passage, the end face o-f the corresponding gear being groovedto simultaneously register with said longitudinal grooves, wherebyliquid is momentarilyl circulated through said bearing at eachrevolution of the gear.

4. A gear pump comprising a casing, a pair of meshing ump gears withinthe casing, said casing having formed therein suction and deliverypassages for liquid pumped by the gears, a pair of shafts for the gears,a bushing interposed between one end of one vof the shafts and thecasing, said bush-v ing having two longitudinal grooves in its innersurface and also having a circumferential groove in its inner surfaceincommunication with the longitudinal grooves, one of thelongitudinalgrooves communicating with the suction passage and the otherwith the delivery passage.

5. A gear pumpA comprising a casing, a pair of meshing pump gears withinthe casing, said casing having formed therein suction and deliverypassages for liquid pumped by the gears, a pair'y of shafts for thegears, a bushlng interposed between one end of one of the shafts and thecasing, said bushing having two longitudinal grooves in its innersurface, one of the longitudinal grooves communicating with the suctionpassage and the other with the delivery passage, and means wherebyliquid is inter-y mittently fed to one of the grooves from the deliverypassage and is drawn back through the vother groove lto thesuctionpassage.

GARFIELD A. WOOD.

